1. Field of the Invention
The present invention relates to a chain lubricating system and, more particularly, to a novel lubricating apparatus for automatically controlling the flow of a given quantity of a lubricant to a preselected area or point on the chain.
2. Brief Description of the Prior Art
As known in the art, industrial type chains, which are employed, for example, in conveyors used for transporting various materials, must be kept well lubricated to prevent binding, excessive wear, and the like. In general, known chain lubricating systems include a source of lubricant and one or more discharge tubes communicating with the lubricant source and having outlets or discharge nozzles directed toward the chain. Means are also typically provided for effecting an intermediate discharge of the lubricant from the lubricant source onto the chain.
In this regard, in recent years much time and research efforts have been expended in an attempt to develop automatic lubricating systems which distribute a lubricant through one or more nozzles to certain preselected points on the chain while the chain is in motion. To a large extent, lubricating apparatus of this type involve the use of a cam action to activate a valve which disperses the lubricant or oil directly onto the chain. Such cam action systems generally comprise a lever or a roller which is displaced by contact with a chain pin or the like, this displacement serving to open a valve causing oil to flow through the lubricant nozzle. Specific examples of such apparatus are disclosed in U.S. Pat. Nos. 3,116,810; 3,171,510; 3,031,033 and 3,785,456. In further designs or proposals, mechanical switches, activated by various means, are employed to open a valve to cause a discharge of a lubricant onto the given chain surface. Thus, in U.S. Pat. No. 3,067,837, a microswitch is contacted by the outer arms of a rotating starwheel to cause periodic opening of a solenoid valve. The arms of the starwheel engage, or mesh with the chain links. In U.S. Pat. No. 3,031,033, a pivotally mounted arm is used in lieu of the starwheel to activate a microswitch.
While many such lubricating systems have been proposed and have achieved, to some extent, commercial acceptance, in general known lubricating apparatus suffer from certain distinct disadvantages. These include overlubrication, lubrication to surfaces that do not require lubrication, misalignment of the lubricant nozzle so that the lubricant misses the chain, damage to synthetic components of the chain by contact with the lubricant and the like. Moreover, and a specific problem to which the present invention is directed, known lubricating systems such as the aforenoted cam acting apparatus, are not adapted and are generally ineffective for modern high speed chain driven apparatus. The present invention is directed to an advance and improvement over prior lubricating apparatus and is uniquely adapted for use in high speed systems.